Baby carriage folding mechanism for a folding baby carriage

ABSTRACT

A casing ( 32 ) included in a baby carriage folding mechanism is mounted on a substantially middle part of the handle of a folding baby carriage. Hinged joints ( 33 ) each having a stationary member ( 34 ) and a movable member ( 35 ) are connected to the opposite ends of the casing ( 32 ), and pipes ( 18 ) forming the handle are connected to the hinged joints ( 33 ), respectively. The pipes ( 18 ) are connected to the movable members ( 35 ) of the joints ( 33 ). Actuating members ( 38   a  and  38   b ) capable of being operated by an operating mechanism included in the casing ( 32 ) are connected to the movable members.( 35 ) of the hinged joints ( 33 ). The actuating members ( 38   a  and  38   b ) turn the movable members ( 35 ) relative to the corresponding stationary members ( 34 ) for folding and developing the folding baby carriage.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a baby carriage folding mechanism for ababy carriage foldable in three and, more particularly to a babycarriage folding mechanism mounted on the handle of a folding babycarriage.

2. A Description of the Related Art

Various folding baby carriages for carrying a baby when taking the babyoutdoors for walking or shopping have been proposed. When necessary, thefolding baby carriages are folded for easy storage and carrying.

When folding the folding baby carriage in a compact package, the userholding the opposite ends of a handle or armrests needs to fold the babycarriage or the user holding a middle part of the handle needs to tiltthe baby carriage so that one side of the baby carriage is folded ontothe other side of the same by gravity, after folding a seat flat.

Accordingly, the user needs to change the position of the hands on thehandle when folding the baby carriage by hand, and the user needs to useboth hands for folding the baby carriage. Therefore, it is difficult forthe user holding a baby in the user's arms to fold the baby carriage.When applying gravity to fold the baby carriage, the baby carriage needsan increased number of joints and the like to reduce resistance againstthe movement of parts when folding the baby carriage. Those jointsreduce the rigidity of the body of the baby carriage and make itdifficult to transmit the sensation of operations and locking of partsto the user.

SUMMARY OF THE INVENTION

According to a first embodiment of the present invention, a babycarriage folding mechanism for a baby carriage foldable in threeincludes a casing and right and left pipes connected to opposite ends ofthe casing by hinged joints, respectively. The pipes compose a handlefor the baby carriage, wherein each of the hinged joints has an innermember on the side of the casing and an outer member capable of turningrelative to the inner member on the side of the pipe. Actuating meansfor turning the outer members relative to the corresponding innermembers are disposed between the casing and the outer members. The babycarriage can be folded or developed by turning the outer membersrelative to the corresponding inner members.

In the baby carriage folding mechanism according to the first embodimentof the present invention, the casing is provided on an inner surfacethereof with guide grooves inclined to the longitudinal axis of thecasing and substantially symmetrical with respect to the center of thecasing. The actuating means comprises actuating members, eachcorresponding to the hinged joint, and sliding in the casing parallel tothe longitudinal axis of the casing. Each of the actuating members has aforward end part pivotally joined to the outer member of the hingedjoint at an eccentric position on the outer member, and a base end partprovided with a projection in engagement with the guide groove of thecasing. And each of the actuating members is moved forward and backwardby turning the casing about its longitudinal axis to turn the outermember of the corresponding hinge.

In the baby carriage folding mechanism according to the first embodimentof the present invention, each of the guide grooves has curvilinearcircumferentially extending portions formed at the starting and theterminating ends thereof.

In the baby carriage folding mechanism according to the first embodimentof the present invention, in an alternative arrangement the guidegrooves are formed with inclinations that are different from each other.

In the baby carriage folding mechanism according to the presentinvention, in a further alternative arrangement each of the guidegrooves has a section on which a large load is loaded, and theinclination of the section with respect to circumferential direction ofthe casing is small.

In the baby carriage folding mechanism according to another embodimentof the present invention, an operating member is placed on the casingfor forward and backward movement. The operating member is provided withsubstantially symmetrical guide grooves inclined relative to a directionin which the operating member is moved. The actuating means comprisesactuating members provided for axial sliding movement in the casing,each with actuating member corresponding to the corresponding hingedjoint. Each of the actuating members has a forward end part pivotallyjoined to the outer member of the hinged joint at an eccentric positionon the outer member, and a base end part provided with a projection inengagement with the guide groove of the operating member, so that theactuating members are moved forward and backward by moving the operatingmember forward and backward to turn the outer members of the hingedjoints.

In the baby carriage folding mechanism according to another embodimentof the present invention, an operating member and a pulley to be turnedby the operating member are provided on the casing. The actuating meanscomprises actuating members provided for axial sliding movement in thecasing, with each actuating member corresponding to a hinged joint. Eachof the actuating members has a forward end part joined pivotally to theouter member of the hinged joint at an eccentric position on the outermember, and a base end part. One of the base end part of the actuatingmember and the pulley is provided with a slot, and the other is providedwith a projection that is engaged with the slot.

In the baby carriage folding mechanism according to another embodimentof the present invention, an operating member and a pulley to be turnedby the operating member are provided on the casing. The actuating meanscomprises an actuating member provided for axial sliding movement in thecasing, wherein the actuating member has opposite ends pivotally joinedto the outer members of the hinged joints at eccentric positions on theouter members, respectively. One of a middle part of the actuatingmember and the pulley is provided with a slot, and the other is providedwith a projection that is engaged with the slot.

In the baby carriage folding mechanism according to another embodimentof the present invention, the actuating means comprises actuatingmembers provided for axial sliding movement in the casing, with eachactuating member corresponding to the hinged joint. Each of theactuating members has a forward end part pivotally joined to the outermember of the hinged joint at an eccentric position on the outer member,and a base end part having a thread or a rack. And a helical gear isinterposed between the base end parts of the actuating members areprovided with the thread or a pinion.

In the baby carriage folding mechanism according to another embodimentof the present invention, the actuating means comprises actuatingmembers provided for axial sliding movement in the casing, with eachactuating member corresponding to the hinged joint. The actuatingmembers are connected to eccentric parts of the outer members of thehinged joints through springs, respectively, and one end of a wire isconnected to each actuating member while the other end of the wire isconnected to a rear end of an armrest attached to each pipe forming thehandle.

The baby carriage folding mechanism according to the present inventionfurther comprises an unlocking mechanism placed in the casing, forunlocking locking members that lock the baby carriage in a developedstate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partly cutaway sectional view of a folding mechanismoperating device in a preferred embodiment according to the presentinvention for a baby carriage;

FIG. 2 is a perspective view of a joint;

FIGS. 3(a) to 3(d) are views showing modifications of grooves formed ina casing;

FIG. 4(a) is a sectional view of a baby carriage folding mechanism in asecond embodiment according to the present invention in a state where anassociated baby carriage is developed;

FIG. 4(b) is a sectional plan view of the baby carriage foldingmechanism shown in FIG. 4(a);

FIG. 4(c) is a sectional view of the baby carriage folding mechanismshown in FIG. 4(a) in a state where the associated baby carriage isfolded;

FIG. 4(d) is a sectional plan view of the baby carriage foldingmechanism shown in FIG. 4(c);

FIG. 5(a) is a schematic view of a baby carriage folding mechanism in athird embodiment according to the present invention in a state where anassociated baby carriage is developed;

FIG. 5(b) is a schematic view of the baby carriage folding mechanismshown in FIG. 5(a) in a state where the associated baby carriage isfolded;

FIG. 6(a) is a plan view of a baby carriage folding mechanism in afourth embodiment according to the present invention;

FIG. 6(b) is a longitudinal sectional view of the baby carriage foldingmechanism shown in FIG. 6(a);

FIG. 6(c) is a view of assistance in explaining the operation of thebaby carriage folding mechanism shown in FIG. 6(a);

FIG. 7 is a schematic view of a baby carriage folding mechanism in afifth embodiment according to the present invention;

FIG. 8 is a view of a modification of the baby carriage foldingmechanism shown in FIG. 7;

FIG. 9 is view of a baby carriage folding mechanism in a sixthembodiment according to the present invention;

FIG. 10 is view of a baby carriage folding mechanism in a seventhembodiment according to the present invention;

FIG. 11 is a perspective view of a baby carriage to which the presentinvention is applied; and

FIG. 12 is a perspective view of the baby carriage shown in FIG. 11folded in three.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A folding baby carriage will be described with reference to FIG. 11showing the folding baby carriage in a perspective view. The babycarriage includes right and left front legs 12 each provided with afront wheel 11, right and left rear legs 14 each provided with a rearwheel 13, a substantially U-shaped handle 30, right and left armrests69, and a guard arm 17 detachably connected to and extended between thearmrests 69. Rear ends of the armrests 69 are pivotally joined to partsof pipes 18 of the handle 30 near the lower ends of the pipes 18. Upperends of the front legs 12 are joined pivotally to front end parts of thearmrests 69. The upper ends of the rear legs 14 are joined pivotally tomiddle parts of the armrests 69. Lower ends of generally L-shapedbrackets 19 are joined pivotally to middle parts of the rear legs 14.The lower ends of the right and the left pipes 18 of the handle 30 arejoined pivotally to middle parts of the brackets 19. When the babycarriage is developed, locking members 20 slidably mounted on lower endparts of the pipes 18 of the handle 30 engage with locking parts formedin upper end parts of the brackets 19 to lock the baby carriage in anexpanded state.

The right and the left front legs 12 are connected by a front connectingrod 21, and the right and the left rear legs 14 are connected by a rearconnecting rod 22. A connecting rod 23 has a front end joined pivotallyto a middle part of each front leg 12, and a rear end joined pivotallytogether with the bracket 19 to the lower end of the pipes 18 of thehandle 30. Middle parts of the right and left connecting rods 23 areconnected by an upper connecting rod 24.

As shown in FIG. 11, the baby carriage is locked in the developed statefor use by bringing the locking members 20 mounted on the lower endparts of the pipes 18 of the handle 30 into engagement with the lockingparts formed in the upper end parts of the brackets 19. When a babycarriage folding mechanism 31 supported on the handle 30 is operated todisengage the locking members 20 from the brackets 19, the armrests 69and the connecting rods 23 can be turned upward about pivotal joiningpoints where the armrests 69 and the connecting rods 23 are joinedpivotally to the vertical sections 18 so that the front legs 12 and therear legs 14 become substantially parallel to each other, whereby thebaby carriage is folded into a package that is easy to carry.

The handle 30, the front connecting rod 21, the rear connecting rod 22and the upper connecting rod 24 are provided in their middle parts withright and left joints and are foldable. The right joints of the handle30, the front connecting rod 21, the rear connecting rod 22 and theupper connecting rod 24 are in a right vertical plane, and the leftjoints of the same are in a left vertical plane. When the right and theleft pipes 18 of the handle 30 are moved forward after extending thefront legs 12 and the rear legs 14 parallel to each other, opposite endportions of the handle 30, the front connecting rod 21, the rearconnecting rod 22 and the upper connecting rod 24 are turned forward andthe baby carriage can be folded into a compact package as shown in FIG.12; that is, the baby carriage can be folded in three.

The baby carriage folding mechanism 31 will be described with referenceto FIG. 1. FIG. 1 shows the baby carriage folding mechanism 31 supportedon a middle part of the handle 30. The pipes 18 of the handle 30 areconnected by joints 33 to the opposite ends, respectively, of a casing32 included in the baby carriage folding mechanism. FIG. 2 is aperspective view of the joint 33. Each joint 33 has a stationary member(inner member) 34 and a movable member (outer member) 35. The movablemember 35 is joined pivotally to the stationary member 34 by a pin 36for turning about the axis of the pin 36 perpendicular to the axis ofthe stationary member 34 (axis of the casing).

The stationary member 34 is provided with grooves 37 a and 37 bextending parallel to the axis of the stationary member 34 indiametrically opposite portions thereof. Actuating members 38 a and 38 bare placed in the grooves 37 a and 37 b, respectively, for sliding alongthe grooves 37 a and 37 b. The actuating members 38 a and 38 b areprovided in their end parts with slots 39 a and 39 b, respectively, asshown in FIG. 1. Pins 40 a and 40 b disposed at eccentric positions onthe movable member 35 are engaged with the slots 39 a and 39 b,respectively. The two pins 40 a and 40 b are disposed diagonallyopposite to each other at positions eccentric with respect to the pin36, and the same are engaged with the slots 39 a and 39 b of theactuating members 38 a and 38 b, respectively. The actuating members 38a and 38 b are provided in their base end parts with projections 41 aand 4lb projecting outwardly from the actuating members 38 a and 38 b,respectively. One end of the pipe 18 of the handle 30 is connected tothe movable member 35.

The two joints 33 thus constructed are disposed so that the axes of thestationary members 34 thereof are aligned with each other, and therespective stationary members 34 of the right and the left joints 33 areconnected by the casing 32. The right and the left stationary members 34are fitted in opposite end parts of the casing 32 so that the casing 32is able to turn relative to the stationary members 34.

Pairs of guide grooves 42 a and 42 b are formed substantiallysymmetrically on the inner circumferences of opposite end parts of thecasing 32. The guide grooves 42 a and 42 b are inclined relative to theaxis of the casing 32 and extend through an angular range of about 90°.The projections 41 a and 41 b projecting from the actuating members 38 aand 38 b are engaged with the guide grooves 42 a and 42 b, respectively.

When the casing 32 is turned about its axis relative to the stationarymembers 34, the projections 41 a and 41 b are moved axially through theguide grooves 42 a and 42 b, so that the actuating members 38 a and 38 bare moved axially. The guide grooves 42 a and 42 b are formed such that,when the casing 32 is turned in one direction, the actuating member 38 aat a position shown in FIG. 1 is moved to the right and the actuatingmember 38 b at a position shown in FIG. 1 is moved to the left to turnthe movable member 35 clockwise as viewed in FIG. 1 to turn the pipe 18of the handle 30 from a folded position indicated by solid lines to adeveloped position indicated by two-dot chain lines in FIG. 1.

When the casing 32 is turned in the opposite direction, the actuatingmember 38 a is moved to the left and the actuating member 38 b is movedto the right to turn the movable member 35 together with the pipe 18 ofthe handle 30 from the developed position indicated by the two-dot chainlines to the folded position indicated by the solid lines in FIG. 1.

An unlocking mechanism including a pulley 45 for disengaging the lockingmembers 20 mounted on the lower end parts of the pipes 18 of the handle30 from the locking parts of the brackets 19 is disposed inside thecasing 32. An operating knob 47 is supported on the casing 32 and isbiased outward by a spring 46. The operating knob 47 is connected to thepulley 45 supported for turning in the casing 32. Ends of wires 48 areconnected to the locking members 20 mounted on the lower end parts ofthe pipes 18 of the handle 30. When the operating knob 47 is depressedagainst the resilience of the spring 46, the wires 48 are pulled todisengage the locking members 20 from the locking parts of the brackets19 so that the baby carriage can be folded.

The operation of the baby carriage folding mechanism will be described.

The operating knob 47 is depressed to disengage the locking members 20from the brackets 19, and the front legs 12 and the rear legs 14 aregathered so as to extend parallel to each other. Subsequently, thecasing 32 is turned so that the operating knob 47 moves upward. Then,the actuating members 38 a and 38 b are moved to the positions indicatedby solid lines in FIG. 1 to turn the pipes 18 of the handle 30 from thepositions indicated by two-dot chain lines to the position indicated bysolid lines in FIG. 1, so that the baby carriage can be folded into thepackage shown in FIG. 12. When the casing 32 is turned in the oppositedirection with the baby carriage in the folded state, the movablemembers 35 turn together with the pipes 18 of the handle 30 from theposition indicated by solid lines to the position indicated by two-dotchain lines in FIG. 1. Thus, the baby carriage can be developed for use.

The baby carriage can be folded or developed only by turning the casing32. Thus, the user is able to fold and develop the baby carriage by aseries of successive operations without letting go of the casing 32 evenonce.

In this embodiment, the guide grooves 42 a and 42 b formed on the innersurface of the casing 32 are curvilinear and inclined relative to theaxis of the casing 32 as shown in FIG. 3(a). The guide grooves 42 a and42 b may have curvilinear circumferentially extending sections extendingfrom starting and terminating ends of the guide grooves 42 a and 42 b asshown in FIG. 3(b) to provide the guide grooves 42 a and 42 b with alocking function to lock the baby carriage in the folded state or thedeveloped state. The guide grooves 42 a and 42 b may be formed atdifferent inclinations, respectively, as shown in FIG. 3(c) to avoid thesynchronous operation of the right joint 33 and the left joint 33 sothat load on the casing 32 in operating the right joint 33 and load onthe casing 32 in operating the left joint 33 are applied to the casing32 during different time ranges, respectively. The guide grooves 42 aand 42 b may be designed so that the inclinations of the sections of theguide grooves 42 a and 42 b corresponding to angular ranges of turningof the casing 32 in which load on the casing 32 increases, are reducedas shown in FIG. 3(d) to reduce torque necessary for turning the casing32.

FIGS. 4(a) to 4(d) show a baby carriage folding mechanism in a secondembodiment according to the present invention. As shown in FIGS. 4(a)and 4(b), a casing 32 is provided with an operating member 50 capable ofmoving in directions perpendicular to the axis of the casing 32. Theoperating member 50 is biased outward by a spring 51. The operatingmember 50 has side walls respectively provided with symmetrical guidegrooves 52 (only one of the guide grooves 52 is shown in FIGS. 4(a) to4(d)). A projection projecting from a part of an actuating member 38 bis engaged with the guide groove 52. This baby carriage foldingmechanism is identical, in other respects, to the folding mechanismoperating device shown in FIG. 1.

When the operating member 50 at a position shown in FIG. 4(a) isdepressed against the resilience of the spring 51 to a position shown inFIG. 4(c), the projection 41 b engaged with the guide groove 52 is movedso that the actuating member 38 b projects from the casing 32.Consequently, the movable members 35 of the right and the left joints 33are turned, and the pipes 18 of the handle 30 are turned to their foldedpositions as shown in FIG. 4(d). Thus, the baby carriage can be folded.

FIGS. 5(a) and 5(b ₁) show a baby carriage folding mechanism in a thirdembodiment according to the present invention including a left actuatingmember 38 b, and a right actuating member 38 b ₂. As shown in FIG. 5(a),an operating member 53 is supported on a casing, not shown, so as to bemovable in directions perpendicular to the axis of the casing. Theoperating member is biased outward by a spring 54. The operating member53 is provided integrally with a leg 53 a. The leg 53 a has a lower endpart provided with a lateral slot 53 b extending along a direction,i.e., a lateral direction in FIG. 5(a), perpendicular to a direction inwhich the operating member 53 can be depressed, i.e., a verticaldirection in FIG. 5(a). A plate (pulley) 56 is supported for turning ona pin 55. A projection attached to the plate 56 is engaged with the slot53 b of the operating member 53.

The plate 56 is provided with projections 58 a and 58 b at symmetricalpositions with respect to the axis of the pin 55. The left actuatingmember 38 b ₁ and the right actuating member 38 b ₂ have base end partsprovided with slots 59 a and 59 b, respectively. The slots 59 a and 59 bextend in a direction, i.e., a vertical direction in FIG. 5(a),perpendicular to the axis of the operating members 38 b ₁, and 38 b ₂.The projection 58 a is engaged with the slot 59 a of the left actuatingmember 38 b ₁ and the projection 58 b is engaged with the slot 59 b ofthe right actuating member 38 b ₂.

When the operating member 53 in a state shown in FIG. 5(a) is depressedagainst the resilience of the spring 54, the plate 56 is turnedclockwise, as viewed in FIG. 5(a), on the pin 55 by the projection 57.Consequently, the actuating members 38 b ₁, and 38 b ₂ are moved awayfrom each other by the projections 58 a and 58 b as shown in FIG. 5(b),so that the movable members 35 are turned to turn the pipes 18 of thehandle 30 to their folded positions, respectively.

The baby carriage folding mechanism shown in FIGS. 5(a) and 5(b)operates both the actuating members 38 b ₁ and 38 b ₂ by the singleplate 56. A baby carriage folding mechanism in a fourth embodimentaccording to the present invention includes an operating member 60provided with two legs 60 a and 60 b, and two plates (pulleys) 61 a and61 b for driving actuating members 38 b ₁ and 38 b ₂ as shown in FIGS.6(a) to 6(c). The plates 61 a and 61 b are turned by the legs 60 a and60 b of the operating member in opposite directions, respectively.

FIG. 7 shows a baby carriage folding mechanism in a fifth embodimentaccording to the present invention. In this baby carriage foldingmechanism, the opposite ends of an actuating member 62 are connected tothe respective movable members 35 a and 35 b of the left and the rightjoints 33. A plate (pulley) 56 is supported for turning on a pin 55 andis provided with projections 57 and 58 a. A leg projecting from a middlepart of the actuating member 62 is provided with a slot extendingvertically, as viewed in FIG. 7, and engaged with the pin 58 a. Anoperating member 53 has a leg 53 a provided with a slot extendinghorizontally, as viewed in FIG. 7 and engaged with the pint 57. When theoperating member 53 is pushed up, as viewed in FIG. 7, the actuatingmember 62 is moved in the direction of the arrow, i.e., to the left, asviewed in FIG. 7. Consequently, the movable members 35 a and 35 b of thejoints 33 are turned in the opposite directions, respectively, to foldthe baby carriage. The operating member 53 is moved down, as viewed inFIG. 7, to develop the baby carriage.

FIG. 8 shows a folding mechanism operating device of a modification ofthe baby carriage folding mechanism shown in FIG. 7. This baby carriagefolding mechanism includes a plate (pulley) 63 having an operating arm63 a which is formed integrally with the plate 63. An actuating member62 can be moved linearly in opposite directions by turning the operatingarm 63 a in opposite directions.

In the baby carriage folding mechanisms shown in FIGS. 5(a) to 8, theactuating member is provided with the slot, the plate is provided withthe projection and the projection is engaged with the slot. The platemay be provided with a slot and the actuating lever may be provided witha projection.

FIG. 9 shows a baby carriage folding mechanism in a sixth embodimentaccording to the present invention. Actuating members 38 b ₁ and 38 b ₂have outer ends pivotally joined to the movable members 35 a and 35 b ofthe joints 33, respectively. Threads (racks) 64 a and 64 b are formed inbase end parts of the actuating members 38 b ₁ and 38 b ₂, a helicalgear (pinion) 65 is interposed between the base end parts of theactuating members 38 b ₁ and 38 b ₂, and the threads (racks) 64 a and 64b are engaged with diametrically opposite parts of the helical gear(pinion) 65. The helical gear (pinion) 65 is turned to move theactuating members 38 b ₁ and 38 b ₂ along the axis to fold or developthe baby carriage.

FIG. 10 shows a baby carriage folding mechanism in a seventh embodimentaccording to the present invention. The respective movable members 35 aand 35 b of the left and the right joints 33 are supported on the pins36. Sliders (actuating members) 67 and 67 b included in the babycarriage folding mechanism are connected by springs to eccentric partsof the movable members 35 a and 35 b which are eccentric with respect tothe pins 36, respectively. The sliders 67 a and 67 b are connected tothe rear ends of the armrests 69 on the sides opposite the sides of themovable members 35 a and 35 b, respectively, by wires 68 a and 68 bextended through the vertical sections 18 of the handle 30.

When the arm rests 69 are turned upwardly to fold the baby carriage, thesliders 67 a and 67 b are pulled through the wires 68 a and 68 b,whereby the springs 66 a and 66 b are stressed. After the armrests 69have been turned to their upper limit positions, the front legs 12 andthe rear legs 14 have been extended substantially parallel to each otherin a double-folded state. When the folding joints in the frontconnecting rod 21, the rear connecting rod 22 and the upper connectingrod 24 are aligned with two vertical planes, the movable members 35 aand 35 b of the joints 33 are turned by the resilience of the stressedsprings 66 a and 66 b and, consequently, the baby carriage is folded inthree. Thus, the baby carriage can be folded in three by operating theoperating knob 47 shown in FIG. 1 to fold the baby carriage in two byturning the opposite side parts of the baby carriage forward.

In the baby carriage capable of being folded in three, each of the fourmembers, i.e., the handle, the front connecting rod, the rear connectingrod and the upper connecting rod has the right and the left foldingjoint, and the folding joints have pins, respectively. An auxiliarydevice, such as a device employing a spring, a device employing a rubbermember, a pneumatic damper or a small motor, may be combined-with eachof the pins of the folding joints to reduce load when operating thefolding joints. Two auxiliary devices may be individually combined withthe pins or a single auxiliary device may be combined with the two pins.

The baby carriage folding mechanism according to the present inventionthus constructed enables the user to fold the baby carriage very easilyin two first and then in three by a series of successive operationswithout letting go of the casing mounted on the handle even once andwithout folding the opposite side parts of the baby carriage by hand.Thus, the user holding a baby is able to fold the baby carriage easily.

What is claimed is:
 1. A folding mechanism for folding a baby carriage,comprising: a casing; first and second pipes connected to opposite endsof said casing via hinged joints, respectively, said first and secondpipes defining a handle for a baby carriage, wherein each of said hingedjoints includes an inner member adjacent to said casing and an outermember adjacent to a respective one of said first and second pipes, withsaid outer member being pivotable relative to said inner member and saidcasing being rotatable about its longitudinal axis relative to saidhinged joints; and actuating structure for pivoting each said outermember relative to a corresponding said inner member, wherein saidactuating structure is connected to said casing and each said outermember such that upon rotation of said casing about its longitudinalaxis said actuating structure causes each said outer member to pivotrelative a corresponding said inner member, whereby the baby carriagecan be folded or unfolded.
 2. The folding mechanism according to claim1, further comprising: guide grooves on an inner surface of said casing,said guide grooves being inclined relative to the longitudinal axis ofsaid casing and being symmetrically arranged relative to a center ofsaid casing, wherein said actuating structure comprises (i) a firstactuating member slidably received within said casing along thelongitudinal axis of said casing, said first actuating member having aforward end part pivotally connected to said outer member of one of saidhinged joints at an eccentric position of said outer member of said oneof said hinged joints, and also having a base end part provided with twoprojections that are engaged with two of said guide grooves,respectively, and (ii) a second actuating member slidably receivedwithin said casing along the longitudinal axis of said casing, saidsecond actuating member having a forward end part pivotally connected tosaid outer member of another of said hinged joints at an eccentricposition of said outer member of said another of said hinged joints, andalso having a base end part provided with two projections that areengaged with another two of said guide grooves, respectively, such thatsaid actuating structure is for pivoting each said outer member relativeto said corresponding said inner member upon rotation of said casing viatravel of said projections within said guide grooves.
 3. The foldingmechanism according to claim 2, wherein each of said guide groovescomprises a curvilinear configuration.
 4. The folding mechanismaccording to claim 3, further comprising a mechanism within said casingfor unlocking locking members which are to lock the baby carriage in anunfolded condition.
 5. The folding mechanism according to claim 2,wherein each of said guide grooves includes a first curvilinearcircumferentially extending portion at a first end thereof, and a secondcurvilinear circumferentially extending portion at a second end thereof.6. The folding mechanism according to claim 5, further comprising amechanism within said casing for unlocking locking members which are tolock the baby carriage in an unfolded condition.
 7. The foldingmechanism according to claim 2, wherein said guide grooves are inclinedrelative to the longitudinal axis of said casing such that one of saidtwo of said guide grooves has an inclination relative to thelongitudinal axis of said casing that is different than an inclinationthat a corresponding one of said another two of said guide grooves haswith the longitudinal axis of said casing.
 8. The folding mechanismaccording to claim 7, further comprising a mechanism within said casingfor unlocking locking members which are to lock the baby carriage in anunfolded condition.
 9. The folding mechanism according to claim 2,wherein each of said guide grooves includes a section at which a largeload is to be applied, with said section having an inclination relativeto a circumferential direction of said casing that is small.
 10. Thefolding mechanism according to claim 9, further comprising a mechanismwithin said casing for unlocking locking members which are to lock thebaby carriage in an unfolded condition.
 11. The folding mechanismaccording to claim 2, further comprising a mechanism within said casingfor unlocking locking members which are to lock the baby carriage in anunfolded condition.
 12. The folding mechanism according to claim 1,further comprising a mechanism within said casing for unlocking lockingmembers which are to lock the baby carriage in an unfolded condition.